Affiliations: [a] Department of Mechanical Engineering, Visvesvaraya National Institute of Technology, Nagpur, Maharashtra, India | [b] Department of Orthodontics, Sharad Pawar Dental College, Wardha, Maharashtra, India
Correspondence:
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Corresponding author: Abhishek M. Thote, Department of Mechanical Engineering, Visvesvaraya National Institute of Technology, South Ambazari Road, Nagpur, Maharashtra 440010, India. Tel.: (+91)8446640525; E-mail: [email protected].
Abstract: Background:Approximately 50% patients with a deep bite possess anatomically extruded mandibular canines. Objective:The objective of this study was to specify an optimum toe (Θ) of the vertical segment of a cantilever from the distal aspect to achieve pure intrusion of a mandibular canine with the segmented arch in lingual orthodontics (LiO). Methods:The geometrical model of a mandibular canine was developed to compute the required values of Θ (positive values – toe-in, negative values – toe-out). Different positions of the cantilever attachment on the lingual bracket top (occlusal) surface were considered according to different heights (h) from the cusp of a canine i.e. 2, 3, 4 and 5 mm in each case of horizontal distance (x) from canine surface i.e. 2 and 3 mm. In x=2mm case, the required values of Θ at h=2,3,4 and 5mm were −5°, 0°, +6° and +11° respectively. While, in x=3mm case, the required values of Θ at h=2,3,4 and 5mm were 0°, +5°, +12° and +17° respectively. Results:In finite element analysis (FEA), the computed values of Θ were verified by displaying the results of a mandibular canine movement in the form of vectors of nodal displacements along with undeformed and deformed models. Conclusions:In the cases of x=2mm and 3mm, no toe angles were required at heights h=3mm and 2mm respectively. Hence, these can be considered as better positions of the cantilever attachment than others.
